1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
m_a_m_a [10]
3 years ago
9

In a collection of nickels, dimes, and quarters worth $6.90, the ratio of the number of nickels to dimes is 3:8. The ratio of th

e number of dimes to quarters is 4:5. Find the number of each type of coin.
Mathematics
1 answer:
dimulka [17.4K]3 years ago
8 0
N=number of nickels
d=number of dimes
q=number of quarters

example
if n:d=3:8
lets say n=3 and d=8
3*8=8*3
so
8n=3d
slightly confusing but go with it, it migh make sense or it might not


n:d=3:8
8n=3d

d:q=4:5
5d=4q

solve for one of them
solve for nickels in first and quarters in second

8n=3d, n=(3/8)d
5d=4q, (4/5)d=q

5n+10d+25q=690
divide by 5 to make it easeir
n+2d+4q=138
sub (3/8)d for n
sub (4/5)d for q
(3/8)d+2d+5(5/4)d=138
(3/8)d+2d+25/4d=138

3/8+2+25/4=
3/8+16/2+50/8=
69/8

(69/8)d=138
times both sides by 8
69d=1104
divide both sides by 69
d=16

16 dimes
sub back

(5/4)d=q
(5/4)16=q
80/4=q
20=q

(3/8)d=n
(3/8)16=n
48/8=n
6=n



6 nickles
16 dimes
20 quarters
yah
You might be interested in
How much will it cost guys
aalyn [17]

Answer:

635 pounds hope you do good :)

Step-by-step explanation:


8 0
3 years ago
Read 2 more answers
If 2/3 is multiplied by a fraction greater than 1, which of these could be the product?
anygoal [31]

The product would need to be greater than 2/3.

6 0
3 years ago
Evaluate 3.6x + 4.5y when x=3 and y=7
Ilya [14]
The answer is 42.3


Step by Step:

Let our variable be n, standing for number.

3.6(x) + 4.5(y) = n
3.6(3) + 4.5(7) = n
10.8 + 31.5 = n
n = 42.3

5 0
3 years ago
Read 2 more answers
Betty has 32 hair ribbons she gave 0.25 of the ribbons to Sheri she gave 0.5 of the remaining ribbons to Marcy she kept the rema
GarryVolchara [31]
Do you mean 25 and 50 percent of the ribbons?

8 0
3 years ago
Read 2 more answers
Alecia earned 48 points on the first quiz and 45 points on the second quiz. What's the percent decrease in her quiz score ?
elixir [45]

Answer:

is the 48 and 45 points out of 100?

7 0
3 years ago
Read 2 more answers
Other questions:
  • Roughly estimate the volume of a tennis ball in cubic centimeters by using 6 for the diameter and 3 for pi. Round the answer to
    9·1 answer
  • A 60 foot ladder is leaned against the side of a building. The bottom of the ladder is 36feet from the building. How high up the
    6·1 answer
  • Which numbers are rational numbers that are not integers?<br><br> 0,4,-2,2/3,-1.8,16,3.2,-5/4
    7·2 answers
  • Mr. Granville needs some plywood that is about three over four-inch thick. Which plywood is closest to three over four-inch thic
    9·1 answer
  • An ordered pair that has a positive x-coordinate and a positive y-coordinate (+ , + ) would be plotted in which quadrant? (Remem
    13·1 answer
  • Find the center and radius of this circle x^2+y^2-6x-10y+30=0
    9·1 answer
  • A person is watching a boat from the top of a lighthouse. The boat is approaching
    14·1 answer
  • What is y + 20 &lt; 180? please help me
    5·2 answers
  • Jim invested $750 in a 3-year CD that earns 4.2% annual interest that is compounded monthly. How much will the CD be
    11·1 answer
  • For problem 8, find the area of the shaded region. The polygon is a regular polygon. please show work.​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!